Magnetoelectric machine



Oct. 8, 1935. w BRADFQRD 2,016,982

MAGNETOELECTRIC MACHINE Filed Oct. 6, 1934 2 Sheets-Sheet l Oct. 8, 1935. w BRADFORD 2,016,982

MAGNETOELECTRIC MACHINE Filed Oct. 6, 1954 2 Sheets-Sheet 2 Patented Oct. s, 1935 UNITED STATES PATENT OFFICE assignor to Wico Electric Company,

West

Srfiigngfield, Mass., a corporation of Massachuse Application October a, 1934, Serial No. 747,216 In Great Britain February 1, 1933 4 Claims. (Cl. 123-449) This invention relates to magneto-electric ma.- chines commonly called magnetos, such as may be conveniently employed in the ignition systems of internal combustion engines, and is especially useful in connection with motorcycles.

It is an object of the invention to provide a magneto-electric machine having an improved.

and simplified drive connection from the crank or other shaft of the internal combustion engine,

and wherein the customary independent operating cam for the interrupter or circuit breaker mechanism is eliminated.

It is a further object of the invention to provide a magneto-electric machine having improved and simplified means for advancing or retarding the spark.

In a magneto-electric machine for internal combustion engines, comprising a rotor member and interrupter or circuit breaker mechanism actuated according to the invention, the crankshaft, camshaft or other shaft of the engine, provides means for positively driving the rotor member of the magneto, and constitutes the sole means for operating the interrupter or circuit breaker mechanism.

The invention consists in providing a driving shaft profiled to afford cam lobes or surfaces which are appropriate for the timed actuation of the interrupter or circuit breaker mechanism and adapted to effect a keying or like drive coupling with the rotor.

The present invention also consists in a magneto-electric machine for internal combustion engines, comprising a rotor member mounted upon an integral extension of the engine crankshaft, camshaft, or other shaft, and interrupter or circuit breaker mechanism operated by a cam member formed in said integral extension. The interrupter or circuit breaker mechanism is mounted upon a base or stator member, which is adjustable relatively with respect to the engine shaft to advance or retard the timing as and when required.

Reference will now be made to the accompanying drawings, in which:

Figure 1 is a front view of a magneto-electric machine for a motorcycle, by way of example, to which the present invention is applied. The machine is shown with its cover removed, and

looking on the end of the engine shaft.

Figure 2 is a perspective-view of an end of a shaft illustrating one form of profiling according to the present invention.

Figure 3 is a perspective view of a convenient form of rotor member adapted for use with the shaft according to Figure 2.

Figure 4 is a rear view of the magneto-electric machine according to Figure 1 when removed from the engine shaft.

Figure 5-is a fragmentary view of a motorcycle engine embodying the equipment shown in Figures 1 to 4.

The invention is shown carried into effect according to one convenient mode, as applied by 10 way of example, to a magneto-electric machine III for a motorcycle, the machine being mounted upon the crank case 34 and adapted to be driven by the engine crankshaft I I.

The machine I0 may be of any suitable form. 16 and, in the example given, has a rotor I2 adapted to be rotated within a stator member indicated generally at I3, and is provided with customary interrupter or circuit breaker mechanism I4.

In order that the engine shaft I I may serve as 20 the drive shaft for the magneto I0, it is provided with, or modified to provide, a special flat surface I5 adjacent one end, as hereinafter described, such as to afford a modified or substantially D-shaped cross-section to the shaft II in 26 the appropriate locality.

The rotor member I2 may comprise straight or bar permanent magnets I6, with or without end laminations I'I disposed about a tube or sleeve (not shown) of non-magnetic material and main- 30 tained in position by end plates I8, I9 of nonmagnetic material.

The rotor member I2 has aiiixed thereto a plate or plates 20, preferably of hardened steel, having a D-shaped hole or holes 2| therein correw sponding to the D-shaped cross-section of the shaft II afforded by the fiat surface I5.

The rotor I2 is thus provided with a positive drive of simple yet efiicient construction. To assemble the rotor I2 in its operating position it 49 is merely slipped over the end of the engine shaft II, which is provided with the surface I5, and it is located in position by means of a spring clip 22 having a projection or the like 23, or with a spring urged detent or the like, which engages a depression 24 suitably located on the engine shaft II.

The shaping or profiling of the D-shaped portion of the shaft II is designed and effected fur- 59 ther to provide a cam lobe 25 for operating the interrupter or circuit breaker mechanism It.

In a particular instance, referred to by way of example only, the fiat or cam surface 25 was provided at an angle of 57 in advance of dead 66 or dead centre position.

The machine may be mounted upon the crank caseortheengineeastinginanydesiredmanner. For example. it may be fixed directly onto the crankcase ll.

According to a preferred method, the base plate 28 o! the machine II is provided with a bore 21 havingabearingfitonabossil ottheengine (see Figure and with lateral extensions or lugs 2|, 3| having arcuate slots ll, 32 therein. The machine may then be bolted down by means or studs or bolts II to the crank case 34, or the engine casting as the case may be, the slots II, 82 providing facility for initially adjusting the setting. a

In a preferred arrangement an adjustment of plus or minus 12% is provided, but any other desired working limits may be obtained.

AsshowninFigureSatlywheel Iiisafiixed to the shaft H on the opposite end from that at which the machine III is located.

Having now described my invention what I claim as new and desire to secure by Letters Patent is:--

i. A magneto-electric machine for internal combustion engines comprising a drive shaft, a stator member provided with a bore or aperture having a bearing fit upon a boss on the engine. and being adjustable rotatively with respect to said drive shaft to advance or retard the timing, a rotor member mounted upon an integral extension of said drive shaft, spring urged means for retaining the rotor member in operative position upon said shaft, and interrupter mechanism operated by a cam member formed in said integral extension.

2. A mamieto-electric machine for internal combustion engines comprising a drive shaft, a stator member provided with a bore or aperture some centre positiontomrnishasparkib" inadvance having a bearing fit upon a boss on the engine and being adjustable rotatively with respect to said drive shaft to advance or retard the timing, laterally extending lugs on said stator mem her having arcuate slots therein whereby the 5 machine may be secured by bolts to the engine in adjusted position, a rotor member and interrupter mechanism, said drive shaft having cam surfaces which are appropriate for the timed actuation of said interrupter mechanism and etiecting a drive coupling with said rotor.

3. A magneto-electric machine (or internal combustion engines comprising a drive shaft, a stator member provided with a bore or aperture having a bearing fit upon a boss on the engine and being adjustable rotatively with respect to said drive shaft to advance or retard the timing, laterally extending lugs on said stator member having arcuate slots therein whereby the machine may be secured by bolts to the engine in adjusted position. a rotor member mounted upon an integral extension of said drive shaft, and interrupter mechanism operated by a cam member formed in said integral extension.

4. A magneto-electric machine for internal combustion engines comprising a drive shaft,

a stator member provided with a bore or aperture having a bearing fit upon a boss on the engine and being adjustable rotatively with respect to said drive shaft to advance or retard the timing, laterally extending lugs on said stator member having arcuate slots therein whereby the machine may be secured by bolts to the engine in adjusted position, a rotor member mounted upon an integral extension of said drive shaft, spring urged means for retaining the rotor member in operative position upon said shaft, and interrupter mechanism operated by a cam member formed in said integral extension.

WILLIAM BRADFORD. 

